Adjacent nucleotides in a polynucleotide chain are joined by
1. N-glycosidic bond
2. Phosphodiester bond
3. O-glycosidic bond
4. Hydrogen bond
Sugars are attached to the pyrimidines by the formation of
1. Hydrogen bond
2. N-glycosidic bond
3. Phosphoester bond
4. O-glycosidic bond
Which of the following process is related to reverse transcription?
1. DNA dependent DNA synthesis
2. RNA dependent DNA synthesis
3. DNA dependent RNA synthesis
4. RNA dependent polypeptide synthesis
Which of the following structures are present in core particle of nucleosome?
1. Octamer of histone proteins
2. 200 bp of DNA
3. Non-histone proteins
4. Linker DNA
Which plant was used by Taylor to prove semiconservative replication at chromosomal level?
2. Vicia faba
Unwinding of DNA creates tension which is released by enzyme
During polymerisation of deoxyribonucleosides triphosphates in bacteria which of the following enzyme is mainly required?
1. DNA dependent RNA polymerase
2. DNA dependent DNA polymerase
3. RNA dependent DNA polymerase
4. DNA gyrase
Poly A tail is present in
1. mRNA of bacteria
2. tRNA of eukaryotes
3. Promotor of bacteria
4. mRNA of eukaryotes
In lac operon, the regulator gene codes for
3. Inactive repressor
4. Active repressor
In the technique of DNA fingerprinting digestion of DNA is followed by
4. Southern blotting
In DNA fingerprinting, detection of hybridised DNA fragments is possible by
If the sequence of one strand of DNA is 5' A T G C A T C G 3', find the sequence of complementary strand in 5' 3' direction
1. T A C G T A G C
2. C G A T G C A T
3. A T G C A T C G
4. A T C G T A C G
Synthesis of leading and lagging strand require
1. Single primer
2. Single and many primers respectively
3. Many and single primers respectively
4. Many primers
What is correct for bacterial transcription?
1. mRNA requires processing to become active
2. Translation can begin when mRNA is fully transcribed
3. Transcription and translation takes place in the same compartment
4. Rho factor initiates the process
The accessibility of promoter regions of bacterial DNA in many cases regulated by the interaction of proteins with sequences termed
2. Structural genes
3. Inhibitor genes
When the genomes of two people are cut using the same restriction enzyme, the length and number of fragments obtained are different, this is called
4. Northern blotting
Which of the following does not code for any proteins?
4. More than one option is correct.
In which step of DNA profiling, nitrocellulose membrane is used?
4. DNA amplification
Which of the following bond is not present in DNA?
1. -1'-9-N-glycosidic bond
2. 3'-5' phosphodiester bond
3. - 1'-1-N-glycosidic bond
4. - 1'-2-N-glycosidic bond
Majority of unusual bases are found in tRNA, loop is
1. First loop from 5'-end of tRNA
2. AA -tRNA synthetase binding loop
3. Ribosomal binding loop
4.. Nodoc site
How many amino acids will be coded by the mRNA sequence -5'CCCUCAUAGUCAUAC3' if a adenosine residue is inserted after nucleotide?
1. Five amino acids
2. Six amino acids
3. Two amino acids
4. Three amino acids
Identification and binding of RNA polymerase to the promoter sequence is a function of
1. Rho factor
2. Sigma factor
3. Beta factor
4. Omega factor
Pribnow box is a consensus of _______ bases, forming a binding site for E. coli RNA polymerase at promotor.
Gene regulation governing lactose operon of E.coli that involves the lac l gene product is
1. Feedback inhibition because excess of -galactosidase can switch off transcription
2. Positive and inducible because it can be induced by lactose
3. Negative and inducible because repressor protein prevents transcription
4. Negative and repressible because repressor protein prevents transcription
Transformation was discovered by
1. Meselson and Stahl
2. Hershey and Chase
4. Watson and Crick
In history of biology, human genome project led to the development of
Select the two correct statements out of the four (a-d) given below about lac operon.
(a) Glucose or galactose may bind with the repressor and inactivate it.
(b) In the absence of lactose the repressor binds with the operator region.
(c) The z-gene codes for permease.
(d) This was elucidated by Francois Jacob and Jacque Monod.
The correct statements are
1. (a) and (b)
2. (b) and (c)
3. (a) and (c)
4. (b) and (d)
Whose experiments cracked the DNA and discovered unequivocally that a genetic code is a "triplet"?
1. Hershey and Chase
2. Morgan and Sturtevant
3. Beadle and Tatum
4. Nirenberg and Mathaei
One gene-one enzyme relationship was established for the first time in
1. Diploccus pneumoniae
2. Neurospora crassa
3. Salmonella typhimurium
4. Escherichia coli
During transcription, RNA polymerase holoenzyme binds to a gene promoter and assumes a saddle -like structure. What is it's DNA-binding sequence?
E. coli cells with a mutated Z gene of the lac operon cannot grow in medium containing only lactose as the source of energy because
1. In the presence of glucose, E. coli cells do not utilize lactose
2. They cannot transport lactose from the medium into the cell
3. The lac operon is constitutively active in these cells
4. They cannot synthesize functional -galactosidase
A single strand of nucleic acid tagged with a radioactive molecule is called
4. Selectable marker
The reaction, Amino acid + ATP Aminoacyl-AMP + P-P depicts
1. Amino acid assimilation
2. Amino acid transformation
3. Amino acid activation
4. Amino acid translocation
In split genes, the coding sequences are called
Out of 64 codons, 61 codons code for 20 types of amino acid. It is called
1. Degeneracy of genetic code
2. Overlapping of genes
3. Wobbling of codons
4. Universality of codons
What would happen if in a gene encoding a polypeptide of 50 amino acids, 25th codon (UAU) is mutated to UAA ?
1. A polypeptide of 24 amino acids will be formed
2. Two polypeptides of 24 and 25 amino acids will be formed
3. A polypeptide of 49 amino acids will be formed
4. A polypeptide of 25 amino acids will be formed
Which antibiotic inhibits interaction between tRNA and mRNA during bacterial protein synthesis?
Haploid content of human DNA contains
1. 4.6 x bp
2. 3.3 x bp
3. 6.6 x bp
4. 3.3 x bp